/*!jQuery Knob*/
/**
 * Downward compatible, touchable dial
 *
 * Version: 1.2.0 (15/07/2012)
 * Requires: jQuery v1.7+
 *
 * Copyright (c) 2012 Anthony Terrien
 * Under MIT and GPL licenses:
 *  http://www.opensource.org/licenses/mit-license.php
 *  http://www.gnu.org/licenses/gpl.html
 *
 * Thanks to vor, eskimoblood, spiffistan, FabrizioC
 */
(function($) {

  /**
   * Kontrol library
   */
  "use strict";

  /**
   * Definition of globals and core
   */
  var k = {}, // kontrol
          max = Math.max,
          min = Math.min;

  k.c = {};
  k.c.d = $(document);
  k.c.t = function(e) {
    return e.originalEvent.touches.length - 1;
  };

  /**
   * Kontrol Object
   *
   * Definition of an abstract UI control
   *
   * Each concrete component must call this one.
   * <code>
   * k.o.call(this);
   * </code>
   */
  k.o = function() {
    var s = this;

    this.o = null; // array of options
    this.$ = null; // jQuery wrapped element
    this.i = null; // mixed HTMLInputElement or array of HTMLInputElement
    this.g = null; // 2D graphics context for 'pre-rendering'
    this.v = null; // value ; mixed array or integer
    this.cv = null; // change value ; not commited value
    this.x = 0; // canvas x position
    this.y = 0; // canvas y position
    this.$c = null; // jQuery canvas element
    this.c = null; // rendered canvas context
    this.t = 0; // touches index
    this.isInit = false;
    this.fgColor = null; // main color
    this.pColor = null; // previous color
    this.dH = null; // draw hook
    this.cH = null; // change hook
    this.eH = null; // cancel hook
    this.rH = null; // release hook

    this.run = function() {
      var cf = function(e, conf) {
        var k;
        for (k in conf) {
          s.o[k] = conf[k];
        }
        s.init();
        s._configure()
                ._draw();
      };

      if (this.$.data('kontroled'))
        return;
      this.$.data('kontroled', true);

      this.extend();
      this.o = $.extend(
              {
                // Config
                min: this.$.data('min') || 0,
                max: this.$.data('max') || 100,
                stopper: true,
                readOnly: this.$.data('readonly'),
                // UI
                cursor: (this.$.data('cursor') === true && 30)
                        || this.$.data('cursor')
                        || 0,
                thickness: this.$.data('thickness') || 0.35,
                width: this.$.data('width') || 200,
                height: this.$.data('height') || 200,
                displayInput: this.$.data('displayinput') == null || this.$.data('displayinput'),
                displayPrevious: this.$.data('displayprevious'),
                fgColor: this.$.data('fgcolor') || '#87CEEB',
                inline: false,
                // Hooks
                draw: null, // function () {}
                change: null, // function (value) {}
                cancel: null, // function () {}
                release: null // function (value) {}
              }, this.o
              );

      // routing value
      if (this.$.is('fieldset')) {

        // fieldset = array of integer
        this.v = {};
        this.i = this.$.find('input')
        this.i.each(function(k) {
          var $this = $(this);
          s.i[k] = $this;
          s.v[k] = $this.val();

          $this.bind(
                  'change'
                  , function() {
                    var val = {};
                    val[k] = $this.val();
                    s.val(val);
                  }
          );
        });
        this.$.find('legend').remove();

      } else {
        // input = integer
        this.i = this.$;
        this.v = this.$.val();
        (this.v == '') && (this.v = this.o.min);

        this.$.bind(
                'change'
                , function() {
                  s.val(s.$.val());
                }
        );
      }

      (!this.o.displayInput) && this.$.hide();

      this.$c = $('<canvas width="' +
              this.o.width + 'px" height="' +
              this.o.height + 'px"></canvas>');
      this.c = this.$c[0].getContext("2d");

      this.$
              .wrap($('<div style="' + (this.o.inline ? 'display:inline;' : '') +
                      'width:' + this.o.width + 'px;height:' +
                      this.o.height + 'px;"></div>'))
              .before(this.$c);

      if (this.v instanceof Object) {
        this.cv = {};
        this.copy(this.v, this.cv);
      } else {
        this.cv = this.v;
      }

      this.$
              .bind("configure", cf)
              .parent()
              .bind("configure", cf);

      this._listen()
              ._configure()
              ._xy()
              .init();

      this.isInit = true;

      this._draw();

      return this;
    };

    this._draw = function() {

      // canvas pre-rendering
      var d = true,
              c = document.createElement('canvas');

      c.width = s.o.width;
      c.height = s.o.height;
      s.g = c.getContext('2d');

      s.clear();

      s.dH
              && (d = s.dH());

      (d !== false) && s.draw();

      s.c.drawImage(c, 0, 0);
      c = null;
    };

    this._touch = function(e) {

      var touchMove = function(e) {

        var v = s.xy2val(
                e.originalEvent.touches[s.t].pageX,
                e.originalEvent.touches[s.t].pageY
                );

        if (v == s.cv)
          return;

        if (
                s.cH
                && (s.cH(v) === false)
                )
          return;


        s.change(v);
        s._draw();
      };

      // get touches index
      this.t = k.c.t(e);

      // First touch
      touchMove(e);

      // Touch events listeners
      k.c.d
              .bind("touchmove.k", touchMove)
              .bind(
                      "touchend.k"
                      , function() {
                        k.c.d.unbind('touchmove.k touchend.k');

                        if (
                                s.rH
                                && (s.rH(s.cv) === false)
                                )
                          return;

                        s.val(s.cv);
                      }
              );

      return this;
    };

    this._mouse = function(e) {

      var mouseMove = function(e) {
        var v = s.xy2val(e.pageX, e.pageY);
        if (v == s.cv)
          return;

        if (
                s.cH
                && (s.cH(v) === false)
                )
          return;

        s.change(v);
        s._draw();
      };

      // First click
      mouseMove(e);

      // Mouse events listeners
      k.c.d
              .bind("mousemove.k", mouseMove)
              .bind(
                      // Escape key cancel current change
                      "keyup.k"
                      , function(e) {
                        if (e.keyCode === 27) {
                          k.c.d.unbind("mouseup.k mousemove.k keyup.k");

                          if (
                                  s.eH
                                  && (s.eH() === false)
                                  )
                            return;

                          s.cancel();
                        }
                      }
              )
              .bind(
                      "mouseup.k"
                      , function(e) {
                        k.c.d.unbind('mousemove.k mouseup.k keyup.k');

                        if (
                                s.rH
                                && (s.rH(s.cv) === false)
                                )
                          return;

                        s.val(s.cv);
                      }
              );

      return this;
    };

    this._xy = function() {
      var o = this.$c.offset();
      this.x = o.left;
      this.y = o.top;
      return this;
    };

    this._listen = function() {

      if (!this.o.readOnly) {
        this.$c
                .bind(
                        "mousedown"
                        , function(e) {
                          e.preventDefault();
                          s._xy()._mouse(e);
                        }
                )
                .bind(
                        "touchstart"
                        , function(e) {
                          e.preventDefault();
                          s._xy()._touch(e);
                        }
                );
        this.listen();
      } else {
        this.$.attr('readonly', 'readonly');
      }

      return this;
    };

    this._configure = function() {

      // Hooks
      if (this.o.draw)
        this.dH = this.o.draw;
      if (this.o.change)
        this.cH = this.o.change;
      if (this.o.cancel)
        this.eH = this.o.cancel;
      if (this.o.release)
        this.rH = this.o.release;

      if (this.o.displayPrevious) {
        this.pColor = this.h2rgba(this.o.fgColor, "0.4");
        this.fgColor = this.h2rgba(this.o.fgColor, "0.6");
      } else {
        this.fgColor = this.o.fgColor;
      }

      return this;
    };

    this._clear = function() {
      this.$c[0].width = this.$c[0].width;
    };

    // Abstract methods
    this.listen = function() {
    }; // on start, one time
    this.extend = function() {
    }; // each time configure triggered
    this.init = function() {
    }; // each time configure triggered
    this.change = function(v) {
    }; // on change
    this.val = function(v) {
    }; // on release
    this.xy2val = function(x, y) {
    }; //
    this.draw = function() {
    }; // on change / on release
    this.clear = function() {
      this._clear();
    };

    // Utils
    this.h2rgba = function(h, a) {
      var rgb;
      h = h.substring(1, 7)
      rgb = [parseInt(h.substring(0, 2), 16)
                , parseInt(h.substring(2, 4), 16)
                , parseInt(h.substring(4, 6), 16)];
      return "rgba(" + rgb[0] + "," + rgb[1] + "," + rgb[2] + "," + a + ")";
    };

    this.copy = function(f, t) {
      for (var i in f) {
        t[i] = f[i];
      }
    };
  };


  /**
   * k.Dial
   */
  k.Dial = function() {
    k.o.call(this);

    this.startAngle = null;
    this.xy = null;
    this.radius = null;
    this.lineWidth = null;
    this.cursorExt = null;
    this.w2 = null;
    this.PI2 = 2 * Math.PI;

    this.extend = function() {
      this.o = $.extend(
              {
                bgColor: this.$.data('bgcolor') || '#EEEEEE',
                angleOffset: this.$.data('angleoffset') || 0,
                angleArc: this.$.data('anglearc') || 360,
                inline: true
              }, this.o
              );
    };

    this.val = function(v) {
      if (null != v) {
        this.cv = this.o.stopper ? max(min(v, this.o.max), this.o.min) : v;
        this.v = this.cv;
        this.$.val(this.v);
        this._draw();
      } else {
        return this.v;
      }
    };

    this.xy2val = function(x, y) {
      var a, ret;

      a = Math.atan2(
              x - (this.x + this.w2)
              , -(y - this.y - this.w2)
              ) - this.angleOffset;

      if (this.angleArc != this.PI2 && (a < 0) && (a > -0.5)) {
        // if isset angleArc option, set to min if .5 under min
        a = 0;
      } else if (a < 0) {
        a += this.PI2;
      }

      ret = ~~(0.5 + (a * (this.o.max - this.o.min) / this.angleArc))
              + this.o.min;

      this.o.stopper
              && (ret = max(min(ret, this.o.max), this.o.min));

      return ret;
    };

    this.listen = function() {
      // bind MouseWheel
      var s = this,
              mw = function(e) {
                e.preventDefault();

                var ori = e.originalEvent
                        , deltaX = ori.detail || ori.wheelDeltaX
                        , deltaY = ori.detail || ori.wheelDeltaY
                        , v = parseInt(s.$.val()) + (deltaX > 0 || deltaY > 0 ? 1 : deltaX < 0 || deltaY < 0 ? -1 : 0);

                if (
                        s.cH
                        && (s.cH(v) === false)
                        )
                  return;

                s.val(v);
              }
      , kval, to, m = 1, kv = {
        37: -1,
        38: 1,
        39: 1,
        40: -1
      };

      this.$
              .bind(
                      "keydown"
                      , function(e) {
                        var kc = e.keyCode;

                        // numpad support
                        if (kc >= 96 && kc <= 105) {
                          kc = e.keyCode = kc - 48;
                        }

                        kval = parseInt(String.fromCharCode(kc));

                        if (isNaN(kval)) {

                          (kc !== 13)         // enter
                                  && (kc !== 8)       // bs
                                  && (kc !== 9)       // tab
                                  && (kc !== 189)     // -
                                  && e.preventDefault();

                          // arrows
                          if ($.inArray(kc, [37, 38, 39, 40]) > -1) {
                            e.preventDefault();

                            var v = parseInt(s.$.val()) + kv[kc] * m;

                            s.o.stopper
                                    && (v = max(min(v, s.o.max), s.o.min));

                            s.change(v);
                            s._draw();

                            // long time keydown speed-up
                            to = window.setTimeout(
                                    function() {
                                      m *= 2;
                                    }
                            , 30
                                    );
                          }
                        }
                      }
              )
              .bind(
                      "keyup"
                      , function(e) {
                        if (isNaN(kval)) {
                          if (to) {
                            window.clearTimeout(to);
                            to = null;
                            m = 1;
                            s.val(s.$.val());
                          }
                        } else {
                          // kval postcond
                          (s.$.val() > s.o.max && s.$.val(s.o.max))
                                  || (s.$.val() < s.o.min && s.$.val(s.o.min));
                        }

                      }
              );

      this.$c.bind("mousewheel DOMMouseScroll", mw);
      this.$.bind("mousewheel DOMMouseScroll", mw)
    };

    this.init = function() {

      if (
              this.v < this.o.min
              || this.v > this.o.max
              )
        this.v = this.o.min;

      this.$.val(this.v);
      this.w2 = this.o.width / 2;
      this.cursorExt = this.o.cursor / 100;
      this.xy = this.w2;
      this.lineWidth = this.xy * this.o.thickness;
      this.radius = this.xy - this.lineWidth / 2;

      this.o.angleOffset
              && (this.o.angleOffset = isNaN(this.o.angleOffset) ? 0 : this.o.angleOffset);

      this.o.angleArc
              && (this.o.angleArc = isNaN(this.o.angleArc) ? this.PI2 : this.o.angleArc);

      // deg to rad
      this.angleOffset = this.o.angleOffset * Math.PI / 180;
      this.angleArc = this.o.angleArc * Math.PI / 180;

      // compute start and end angles
      this.startAngle = 1.5 * Math.PI + this.angleOffset;
      this.endAngle = 1.5 * Math.PI + this.angleOffset + this.angleArc;

      var s = max(
              String(Math.abs(this.o.max)).length
              , String(Math.abs(this.o.min)).length
              , 2
              ) + 2;

      this.o.displayInput
              && this.i.css({
                'width': ((this.o.width / 2 + 4) >> 0) + 'px'
                ,
                'height': ((this.o.width / 3) >> 0) + 'px'
                ,
                'position': 'absolute'
                ,
                'vertical-align': 'middle'
                ,
                'margin-top': ((this.o.width / 3) >> 0) + 'px'
                ,
                'margin-left': '-' + ((this.o.width * 3 / 4 + 2) >> 0) + 'px'
                ,
                'border': 0
                ,
                'background': 'none'
                ,
                'font': 'bold ' + ((this.o.width / s) >> 0) + 'px Arial'
                ,
                'text-align': 'center'
                ,
                'color': this.o.fgColor
                ,
                'padding': '0px'
                ,
                '-webkit-appearance': 'none'
              })
              || this.i.css({
                'width': '0px'
                ,
                'visibility': 'hidden'
              });
    };

    this.change = function(v) {
      this.cv = v;
      this.$.val(v);
    };

    this.angle = function(v) {
      return (v - this.o.min) * this.angleArc / (this.o.max - this.o.min);
    };

    this.draw = function() {

      var c = this.g, // context
              a = this.angle(this.cv)    // Angle
              , sat = this.startAngle     // Start angle
              , eat = sat + a             // End angle
              , sa, ea                    // Previous angles
              , r = 1;

      c.lineWidth = this.lineWidth;

      this.o.cursor
              && (sat = eat - this.cursorExt)
              && (eat = eat + this.cursorExt);

      c.beginPath();
      c.strokeStyle = this.o.bgColor;
      c.arc(this.xy, this.xy, this.radius, this.endAngle, this.startAngle, true);
      c.stroke();

      if (this.o.displayPrevious) {
        ea = this.startAngle + this.angle(this.v);
        sa = this.startAngle;
        this.o.cursor
                && (sa = ea - this.cursorExt)
                && (ea = ea + this.cursorExt);

        c.beginPath();
        c.strokeStyle = this.pColor;
        c.arc(this.xy, this.xy, this.radius, sa, ea, false);
        c.stroke();
        r = (this.cv == this.v);
      }

      c.beginPath();
      c.strokeStyle = r ? this.o.fgColor : this.fgColor;
      c.arc(this.xy, this.xy, this.radius, sat, eat, false);
      c.stroke();
    };

    this.cancel = function() {
      this.val(this.v);
    };
  };

  $.fn.dial = $.fn.knob = function(o) {
    return this.each(
            function() {
              var d = new k.Dial();
              d.o = o;
              d.$ = $(this);
              d.run();
            }
    ).parent();
  };

})(jQuery);